1. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics
2. National Center for Magnetic Resonance in Wuhan
3. Wuhan Institute of Physics and Mathematics
4. Chinese Academy of Sciences
5. Wuhan 430071
6. State Key Laboratory of Organic-Inorganic Composites
7. Beijing University of Chemical Technology
8. Beijing 100029
9. P. R. China